2023 Mineral Reserves & Resources:
Summary of Improvements at Cangrejos Deposit Since 2020 PEA:
- Contained ounces of gold in the mine plan increased to 11.6 Moz
- Indicated gold mineral resource increased to 16.8 Moz from 10.4 Moz
- Mineral resource expansion makes Cangrejos 26th largest primary gold asset globally
Click here to view the supporting NI 43-101 technical report.
Table 1: Estimate of Mineral Resource – Cangrejos & Gran Bestia Deposit (0.25 g/t Au Eq Cut-off) – Inclusive of Mineral Reserves
| Category | Million Tonnes | Average Grade | Contained Metals | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Au (g/t) | Cu (%) | Ag (g/t) | Mo (ppm) | Au (Moz) | Cu (Mlbs) | Ag (Moz) | Mo (Mlb) | ||
| Indicated | 1079.9 | 0.48 | 0.09 | 0.7 | 17.8 | 16.8 | 2,166 | 24.3 | 42.4 |
| Inferred | 296.3 | 0.39 | 0.07 | 0.7 | 11.7 | 3.7 | 483 | 7.0 | 7.6 |
Mineral Resource Estimate Notes:
(1) The mineral resource estimate has an effective date of January 30, 2023. (2) Mineral resources that are not mineral reserves do not have demonstrated economic viability. (3) The mineral resources in this estimate were calculated with the Canadian Institute of Mining, Metallurgy and Petroleum (“CIM”) Definition Standards for Mineral Resources and Mineral Reserves (2014) and the CIM Estimation of Mineral Resources and Mineral Reserve Best Practice Guidelines (2019). (4) Gold equivalent values were calculated using the following prices: a gold price of $1,600 per ounce, a copper price of $3.50 per pound, a molybdenum price of $11.00 per pound and a silver price of $21.00 per ounce. Gold equivalent values can be calculated using the following formula: AuEq = Au g/t + (Ag g/t x 0.0131) + (Cu % x 1.50) + (Mo ppm / 10,000 x 4.71) x 0.97. (5) Using the assumed metal prices, operating costs, and metallurgical recoveries, the base case cut-off grade for mineral resources is estimated to be 0.25 g/t AuEq. (6) The indicated and inferred mineral resources are contained within a limiting pit shell and comprise a coherent body. There are no adjustments for mining losses or dilution. (7) It is reasonably expected that the majority of inferred mineral resources could be upgraded to indicated mineral resources with continued exploration. (8) Lumina is not aware of any legal, political, environmental, or other risks that could materially affect the potential development of the mineral resources.
This mineral resource estimate was prepared in accordance with NI 43-101 and was based on a total of 98,759 metres of diamond drilling in 280 holes. Of these, 90,142 metres in 248 holes were drilled by Lumina, 5,595 metres in 22 holes were drilled by the Project’s previous operator, Newmont Mining Corporation (“Newmont”), in joint venture with Lumina’s predecessor company, Odin Mining and Exploration Ltd (“Odin”), and 3,022 metres in 10 holes were drilled by Odin after the joint venture was dissolved. Indicated and inferred mineral resources are estimated using a three-dimensional block model with a nominal block size of 15 x 15 x 15 metres. Drill holes penetrate the Cangrejos deposit and Gran Bestia deposit at a variety of orientations to depths approaching 750 metres below surface. The mineral resource estimate was generated using drill hole sample assay results and the interpretation of a geological model which relates to the spatial distribution of gold, copper, silver and molybdenum. Interpolation characteristics were defined based on the geology, drill hole spacing, and geostatistical analysis of the data. The effects of potentially anomalous high-grade sample data, composited to two metre intervals, are controlled using both traditional top-cutting as well as limiting the distance of influence during block grade interpolation. Block grades are estimated using ordinary kriging and have been validated using a combination of visual and statistical methods. Resources in the indicated mineral resource category are delineated by drilling spaced at maximum 100 metre intervals. Resources in the inferred mineral resource category are within a maximum distance of 150 metres from a drill hole. The estimate of the indicated and inferred mineral resource is constrained within a limiting pit shell derived using projected technical and economic parameters.
Table 2: Probable Mineral Reserves – Cangrejos & Gran Bestia Deposits (Declining NSR Cut-off from $23 – $7.76/tonne milled) – included within Mineral Resource
| Probable Reserves | Million Tonnes | NSR ($/t) | Average Grade | Contained Metals | ||||
|---|---|---|---|---|---|---|---|---|
| Au (g/t) | Cu (%) | Ag (g/t) | Au (Moz) | Cu (Mlbs) | Ag (Moz) | |||
| Saprolite & Saprock | – | – | – | – | – | – | – | – |
| Partially Oxidized | 18 | 23.07 | 0.57 | 0.09 | 0.80 | 0.34 | 36 | 0.48 |
| Fresh Rock | 639 | 24.80 | 0.55 | 0.10 | 0.68 | 11.22 | 1384 | 13.90 |
| Total Mineral Reserves | 659 | 24.76 | 0.55 | 0.10 | 0.69 | 11.56 | 1421 | 14.38 |
Mineral Reserve Estimate Notes:
(1) The mineral reserve estimate has an effective date of March 30, 2023. (2) Mineral reserves on Table 6 are contained within the mineral resource estimate, (3) The mineral reserves in this estimate are based on declining NSR cut-off grade between $23.00/t milled to $7.76/t milled. (4) Net Smelter Return (“NSR”) values were calculated using the following prices: a gold price of $1,500 per ounce, a copper price of $3.00 per pound and a silver price of $18.00 per ounce. NSR values are calculated using the following costs & recoveries: Costs of metal in copper concentrate: $7.50/oz Au, $0.51/lb Cu and $0.65/oz Ag; Costs of metal in dore: $0.30/oz Au and $0.30/oz Ag; Recoveries of metal in copper “oxide” rock concentrate: 60% Au, 50% Ag and 50% Cu; Recoveries of metal in copper “fresh” rock concentrate: 62% Au, 50% Ag and 86% Cu; Recoveries of metal in copper “oxide” rock dore: 20% Au and 10% Ag; Recoveries of metal in copper “fresh” rock dore: 20% Au and 20% Ag; Payables of metal in copper concentrate: 97.5% Au, 60% Ag and 93.58% Cu; Payables of metal in dore: 99.95% Au and 99.5% Ag; (5) The mineral reserves estimate were calculated with the Canadian Institute of Mining, Metallurgy and Petroleum (“CIM”), CIM Standards on Mineral Resources and Reserves, Definitions and Guidelines prepared by the CIM Standing Committee on Reserve Definitions. (6) The probable mineral reserves are contained within an engineered pit design that is based on a pit optimization associated with an $1,100/oz gold price. (7) Gold is reported in millions of troy ounces and the gold grade is reported in grams per metric tonne (8) Totals may not add up due to rounding. (9) The qualified person for the mineral reserve estimate is Joseph McNaughton P.E., a Senior Engineer at Independent Mining Consultants, Inc. (10) Lumina is not aware of any legal, political, environmental, or other risks that could materially affect the potential development of the mineral reserves.
This mineral reserve estimate was prepared in accordance with NI 43-101. The mineral reserves are contained within an engineered pit design. The engineered pit was designed based on the geotechnical slope guidance provided by Wyllie & Norrish Engineers, Inc. The engineered pit incorporates access and sufficient working room for the planned fleet. The mineral reserves are reported from a twenty-five-and-a-half-year mine plan that has been scheduled based on a declining NSR cut-off grade strategy produced from seven engineered phase designs (pits/pushbacks). The phase designs were developed from pits that were optimized to increasing metal prices. The final (ultimate) pits targeted optimized pits consistent with $1,000 to $1,100/oz gold prices.
Qualifed Person
Leo Hathaway, P.Geo, a “qualified person” within the definition of that term in NI 43-101, has reviewed and approved the scientific and technical information contained on this page.
